Re: [RFC net-next v3 3/3] net: dsa: microchip: implement PHY loopback configuration for KSZ8794 and KSZ8873

[Vladimir Oltean]

On Fri, Jan 12, 2024 at 03:07:16PM +0100, Oleksij Rempel wrote:
> Correct the PHY loopback bit handling in the ksz8_w_phy_bmcr and
> ksz8_r_phy_bmcr functions for KSZ8794 and KSZ8873 variants in the ksz8795
> driver. Previously, the code erroneously used Bit 7 of port register 0xD
> for both chip variants, which is actually for LED configuration. This
> update ensures the correct registers and bits are used for the PHY
> loopback feature:
> 
> - For KSZ8794: Use 0xF / Bit 7.
> - For KSZ8873: Use 0xD / Bit 0.
> 
> The lack of loopback support was seen on KSZ8873 system by using
> "ethtool -t lanX". After this patch, the ethtool selftest will work,
> but only if port is not part of a bridge.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
> ---

Reviewed-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>